Não informado. (1976). Annual Bulletin of Trade in Chemical Products. United Nations, Economic Commission for Europe.
Chicago-referens (17:e uppl.)Não informado. Annual Bulletin of Trade in Chemical Products. New York: United Nations, Economic Commission for Europe, 1976.
MLA-referens (8:e uppl.)Não informado. Annual Bulletin of Trade in Chemical Products. United Nations, Economic Commission for Europe, 1976.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.